Natural diamond sources have been discovered in approximately 35 different countries around the World across several continents. Diamonds, and consequently mines like the Mirna Diamond Mine in Russia, are found in areas where there have been volcanic activity or erosion and where natural elements such as streams, rivers and even glaciers might have taken them. While in operation the mine yielded 2 million carats every year. The Mirna mine is now famous as the world's largest man-made hole.